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Question

Hey all i am working on a database project for a class (im just learning sql)

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What i am doing successfully

1: Reading an event XML feed from another website and placing it into the database (via php)

(internal id is controlled by me and needed externalinstance_id is pulled from the feed and i want it to insert if not exists)

http://i.imgur.com/rKrRBQ8g.png

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what am i trying to do?

1: The events have their own eventinstance_id (i want to use this to insert only unique) , and i Have my own Internal ID, how do i "insert if external_id is not in the database" (ignore duplicated)

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what i tried so far:

1: A select where not exists in phpmyadmin(trying to build the query) however when i perform the query i get this error on phpmyadmin

*different table same idea (my testing table)

http://i.imgur.com/unkURL5.png

(i want to insert iff there isnt a internal_id of 2 for example... (same project different table same idea of what i need to do) )

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Server

Win 7 (i know)

Apache 2.4.18

PHP 7.0.6

PHP EXT mysqli

phpmyadmin 4.5.1

Thanks in advanced (may or may not be a stupid question)

Answer 1

Make eventinstance_id as Unique Id and use can use "INSERT IGNORE" QUERY. It will insert only unique values.

Example :- INSERT IGNORE INTO table (pid,uid,data) VALUES (1,34,56); Where pid is primary key and uid is unique key.

Below you can find more details on Insert Ignore "INSERT IGNORE" vs "INSERT ... ON DUPLICATE KEY UPDATE"